Home / 1,680.40-2,318.92-981.76

Finding the Fourth Proportional to 1,680.40, 2,318.92 and 981.76

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Solution

The fourth proportional to 1,680.40, 2,318.92 and 981.76 is: 1,354.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,680.40 : 2,318.92 = 981.76 : x
  2. Step 2: Convert to fraction form
    1,680.40/2,318.92 = 981.76/x
  3. Step 3: Cross multiply
    1,680.40x = 2,318.92 × 981.76
  4. Step 4: Simplify right side
    1,680.40x = 2,276,622.90
  5. Step 5: Solve for x
    x = 2,276,622.90/1,680.40
  6. Step 6: Final answer
    x = 1,354.81

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.